Cellular Update Failed

Dears,

I have a problem in my iPhone 7, from three day ago I have no service to my Carrier and my iPhone show a message " Cellular Update Failed - Your iPhone cannat make and receive calls or access cellular data until it has been updated "

I have the last update 12.2 and I connected my iPhone to iTunes with no another update available.

Please I need to help me and solve my problem without lose my data.